So, I complained to Oxford and after some detailed discussion they gave me the value as a credit on their website (with free delivery). So can't fault that service.

Separately I got RiffRaff's cheap chinese ones. They seem better.Not fitted yet as they wont fit on the clutch side without a different bracket. I need to find or adapt one. They will work with the stock bar ends if I can sort the bracket on the other end (Its supposed to fit to the mirror stalk but it doesn't reach on mine).